Too young to explain, 13-month-old Lindsey crouched on her knees, grabbing her belly. She lay on the floor, rolling around, screaming.

Then came “really nasty diarrhea; it was like water,” her mother, Cassandra Wobith, said. Two days later, “she started having really bloody diarrhea. It was literally nothing but blood. Just blood.”

Her baby daughter, who drank formula mixed with tap water, had been poisoned by Alamosa’s water supply. Lindsey was one of more than 400 people sickened last year by salmonella bacteria, the worst disease outbreak from drinking water anywhere in the United States since 2004.

In the aftermath:

• Health investigators discovered an in-ground storage tank was cracked at the corners and had a hole in its side — potential entry points for a strain of salmonella bacteria found in animal feces. A state inspection of Alamosa’s water system months before the outbreak failed to include a detailed look at this tank. As a result, its interior had not been physically inspected in 11 years.

• The state canceled a 34-year-old exemption that allowed Alamosa to pump untreated drinking water through a delivery system almost a century old. It also ordered the city to improve inspections of its water system.

• Alamosa opened a treatment plant designed to remove traces of arsenic detected in its water for 13 years. The new plant also disinfects water. Had it been completed months earlier, the city could have avoided the salmonella epidemic.

A year later, the Colorado Department of Public Health and Environment has not pinpointed where salmonella bacteria invaded the water supply of a city of 9,000 people. But crumbling infrastructure is a prime suspect.

After tests detected coliform bacteria in Alamosa’s cracked storage tank, the city disconnected it from its drinking-water supply. A 75-year-old water tower was missing bolts and needed repairs on a roof stained by bird droppings.

The city had 50 miles of underground pipes, and “a lot of pipes were World War I vintage. They’re old. They’re very old,” said Steve Gunderson, the health department’s water- quality director. “That’s the problem with our nation’s infrastructure.”

History of untreated water

The health department had exempted Alamosa from chlorination because the city drew its water from deep aquifers presumably impervious to bacteria. But Alamosa’s distribution system was not impervious, and the city now chlorinates every drop of drinking water.

The department is reviewing about 90 smaller drinking-water supplies that have chlorination waivers. It has revoked eight waivers already after finding bacteria in distribution systems or other sanitary deficiencies.

Don Koskelin, Alamosa’s public- works director, suspects animals defecated on or around the in-ground tank, and when winter snow melted, deadly bacteria slipped through cracks in the concrete.

He laments that the epidemic struck just before Alamosa completed its water-treatment plant.

“It’s really ironic — six months later, this couldn’t have happened. In six months we would have been there,” he said.

Alamosa delivered untreated water from deep underground sources to storage tanks, water mains and home faucets.

But test samples of its natural water began detecting a potential pollutant in 1995: arsenic. Thirteen years later, the city finally completed a treatment plant that removes arsenic — and chlorinates drinking water to kill bacteria.

Why did it take so long?

According to state health officials, Alamosa’s drinking water violated arsenic limits when the federal government tightened that standard at the end of the Clinton administration. The Bush administration then decided to review that decision, postponing enforcement of a standard that the administration ultimately upheld.

In 2005, Alamosa agreed to build a $12.6 million water-treatment system that would remove arsenic, but the city first had to go to voters for approval of a bond issue.

Plant construction began in 2007. The salmonella epidemic struck in March 2008, months before it opened.

Flood of damage claims

A year later, Alamosa faces dozens of damage claims from people sickened by its drinking water.

Louise Malouff is one. She was sick for a week. So was her 3-year-old son, who suffered through stomach cramps, vomiting and diarrhea.

Her 6-year-old son had it the worst. “He woke up on a Saturday, didn’t want to eat,” she said. “He kept getting up and going to the restroom. I asked him, ‘Are you OK?’ He goes, ‘No, I’m pooping blood.’ ”

She called his pediatrician, who advised her to keep him hydrated and bring him in on Monday. But “the diarrhea, it just continued,” she said. “He was to a point where he was sitting on a pot and holding a trash can and vomiting at the same time, and crying.”

Fearing her son might need a blood transfusion, she took him to the hospital, where they waited four hours in a crowded emergency room.

Cassandra Wobith also filed a claim. Her baby daughter, Lindsey, was sick for two weeks, crying day and night, her bottom raw from diarrhea. Her youngest son was sick. She was sick and lost weeks of wages at a nursing home.

The epidemic spared her oldest son and her husband, but “it was pretty hard for the kids,” she said. “We had to turn the faucets off because they were used to getting water from the tap. They didn’t understand they couldn’t drink the water.”

“It was the worst pain I’ve ever felt,” she said. “I end up in the hospital emergency room with the salmonella, very dehydrated, missed a whole week of work. My restaurant closed for about three weeks.”

The hospital has handed her emergency room bill to a collection agency, the city has told her she missed the deadline for claiming damages, and “I’m really disappointed in the city of Alamosa, the way they handled this,” she said. “I think they should be accountable for what they did.”

City officials say state law set the deadline, and they weren’t inviting residents to sue them.

The salmonella epidemic struck young children and older adults particularly hard. Larry Velasquez, a 55-year- old man who was ill already, died after the bacteria invaded his body.

Koskelin, the city public-works director, said a state inspector who reviewed Alamosa’s water system seven months before the outbreak never checked its in-ground tank carefully.

“Did he do a detailed inspection of the tank? No, he did not,” Koskelin said.

Ron Falco, Colorado’s drinking water program manager, said the state inspector did notice the fenced tank, but a city operator explained that it was going to be removed from the drinking water system in a few months.

No tank deficiencies were noted in the state inspection report. During the salmonella outbreak, most of the water Alamosa residents were drinking passed through that reservoir.

When it was examined afterward, “all four corners were in pretty bad shape. If you were inside the tank, you could look out. Light would penetrate,” Falco said.

Small towns resist chlorine

The state identified 442 cases of “probable salmonella infections” from the single water supply. Those cases may represent a fraction of the people affected. A community survey found 20 percent of all residents in Alamosa, nearly 2,000 people, reported symptoms of gastrointestinal illnesses during the epidemic.

State health officials say thousands of systems in the United States that draw drinking water from underground sources are not required to disinfect it.

In Colorado, getting towns that have never done so to add chlorine can be a challenge.

“These tend to be big battles,” Gunderson said. Disinfection can add the unwelcome taste of chlorine, and “it also involves cost.”

In Alamosa, city officials say they are getting more complaints about chlorination than they did about salmonella.

“The chlorine, people don’t like the chlorine,” City Manager Nathan Cherpeski said. “The water used to taste really, really good.”

The 90 public-water systems exempted from disinfection in Colorado include schools, campgrounds, resorts, water districts, two state parks and 15 small cities and towns that rely on deep wells. Some have begun chlorinating their water voluntarily.

One exempted system lies 17 miles west of Alamosa, where 4,000 Monte Vista residents drink untreated water.

“We’re quite comfortable not chlorinating,” said Randy Martin, the city’s public-works director. “Our system is quite different than the system that had problems.”

Unlike Alamosa, “we have no storage units where you could get contamination from outside sources,” he said.

Monte Vista tests its water monthly for bacteria.

Holyoke city superintendent Mark Brown said it does add a trace of chlorine to kill a harmless type of bacteria occasionally detected in water tests — but less than state chlorination standards would require.

Holyoke draws all its water from deep wells, and “we have an elevated storage tank only,” he said.

In Denver, the historic Brown Palace Hotel has served untreated water from an artesian well 720 feet deep since it opened 116 years ago.

Spokeswoman Shannon Hulsey said the hotel began paying for weekly water tests about 18 months ago and spent $157,000 last year for a backup chlorination system in case bacteria is ever detected.

“It’s been 100 percent clean ever since we started testing,” she said.

David Olinger is an investigative journalist who has worked for newspapers in New Hampshire, Florida and Colorado since 1976. In 18 years in Colorado, he has covered a variety of subjects for The Denver Post.

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